Escherichia coli succinate dehydrogenase variant lacking the heme b
- 13 November 2007
- journal article
- Published by Proceedings of the National Academy of Sciences in Proceedings of the National Academy of Sciences
- Vol. 104 (46) , 18007-18012
- https://doi.org/10.1073/pnas.0707732104
Abstract
The Escherichia coli enzyme succinate:ubiquinone oxidoreductase [(succinate dehydrogenase (SdhCDAB)] couples succinate oxidation to ubiquinone reduction and is structurally and functionally equivalent to mitochondrial complex II, an essential component of the aerobic respiratory chain and tricarboxylic acid cycle. All such enzymes contain a heme within their membrane anchor domain with a highly contentious, but as-yet-undetermined, function. Here, we report the generation of a complex II that lacks heme, which is confirmed by both optical and EPR spectroscopy. Despite the absence of heme, this mutant still assembles properly and retains physiological activity. However, the mutants lacking heme are highly sensitive to the presence of detergent. In addition, the heme does not appear to be involved in reactive oxygen species suppression. Our results indicate that redox cycling of the heme in complex II is not essential for the enzyme's ubiquinol reductase activity.Keywords
This publication has 38 references indexed in Scilit:
- The Quinone Binding Site in Escherichia coli Succinate Dehydrogenase Is Required for Electron Transfer to the Heme bJournal of Biological Chemistry, 2006
- The Iron-Sulfur Clusters in Escherichia coli Succinate Dehydrogenase Direct Electron FlowPublished by Elsevier ,2006
- 3-Nitropropionic Acid Is a Suicide Inhibitor of Mitochondrial Respiration That, upon Oxidation by Complex II, Forms a Covalent Adduct with a Catalytic Base Arginine in the Active Site of the EnzymeJournal of Biological Chemistry, 2006
- Electron Transfer within Complex IIJournal of Biological Chemistry, 2005
- Crystallographic Studies of the Escherichia coli Quinol-Fumarate Reductase with Inhibitors Bound to the Quinol-binding SiteJournal of Biological Chemistry, 2002
- Retention of Heme in Axial Ligand Mutants of Succinate-Ubiquinone Oxidoreductase (Complex II) from Escherichia coliPublished by Elsevier ,2001
- Abortive assembly of succinate-ubiquinone reductase (Complex II) in a ferrochelatase-deficient mutant of Escherichia coliMolecular Genetics and Genomics, 2001
- Localization of Histidine Residues Responsible for Heme Axial Ligation in Cytochrome b556 of Complex II (Succinate:Ubiquinone Oxidoreductase) in Escherichia coliBiochemistry, 1998
- Resolution and Reconstitution of Succinate-Ubiquinone Reductase from Escherichia coliJournal of Biological Chemistry, 1997
- Two Hydrophobic Subunits Are Essential for the Heme b Ligation and Functional Assembly of Complex II (Succinate-Ubiquinone Oxidoreductase) from Escherichia coliPublished by Elsevier ,1996